Stand with your feet together, arms by your sides. Brace your abs.
Hinging from your hips, lean forward and place your hands on the floor. Depending on your hamstring flexibility, you may need to bend your knees a little (or a lot!) to do this.
Taking small steps, walk your hands forward as far as you can while maintaining your core stability. Do not let your hips drop or extend your lumbar spine. Brace those abs! The further you walk your hands beyond your shoulders, the harder this exercise becomes. Hold this furthest point for a couple of seconds.
Without relaxing your core, walk your hands back toward your feet and stand up. If you prefer, you can keep your hands on the floor and then transition immediately into another rep.